Washington Revised Code Title 7. Special Proceedings and Actions § 7.36.020. Parents, guardians, etc., may act for minors, persons under guardianship or conservatorship

Writs of habeas corpus shall be granted in favor of parents, guardians, limited guardians where appropriate, spouses or domestic partners, and next of kin, and to enforce the rights, and for the protection of minors and persons who have been placed under a guardianship under RCW 11.130.265 or under a conservatorship under RCW 11.130.360; and the proceedings shall in all cases conform to the provisions of this chapter.